1. Field of the Invention
The present invention relates to self-sealing valves, and in particular, it relates to self-sealing valves for use with fill tubes.
2. Description of the Prior Art
In recent developments in inflatable prosthetic devices, it has been found desirable to progressively inflate the prosthetic device over a period of time. This has required the use of subcutaneous injection sites connected to the inflatable prosthetic device by a fill tube. The fill tube is typically inserted into the inflation chamber of the device through a valve. The valve is typically made of two sheets of silicone rubber bonded together along their edges with a channel therebetween. If a fill tube is disposed within the valve for a long time, stresses in the silicone rubber forming the channel result in the valve not sealing adequately once the fill tube is removed. The channel becomes somewhat "set" in an open position and remains in the set position once the fill tube has been removed.
A number of patents directed to prosthetic inflatable devices show valves which are constructed of two sheets of silicone elastomer bonded together along two edges to form a channel. None of the valves illustrated in the immediately below-listed patents are constructed to avoid the channel being permanently deformed due to the stress caused on the material by the fill tube inserted into the channel over a long period of time:
______________________________________ Inventor U.S. Pat. No. ______________________________________ Hyans 4,459,318 Bejarano 4,263,682 Cox, Jr. 4,178,643 Koneke et al 3,852,833 McGhan et al 3,852,832 Valliancourt et al 3,565,078 Krueger 2,697,229 ______________________________________
The Lynch U.S. Pat. No. 3,883,902 and the Boone U.S. Pat. No. 3,600,718 show other types of valves used in inflatable prosthetic devices. The valve illustrated in the Lynch Patent shows a complicated sealing arrangement and the valve shown in the Boone Patent shows a valve using a silicone gel chamber as a sealing arrangement.
Still other patents show inflatable devices other than prosthetic devices using a variety of valving arrangements for the introduction of air. However, similar to the patents directed to prosthetic devices, the valves shown in the immediately below-listed patents are also not designed for the retention of a fill tube for a long period of time.
______________________________________ Inventor U.S. Pat. No. ______________________________________ Kampa 3,584,671 Mirando 3,523,563 Mondano 3,410,300 Nicholls 3,204,959 Siedow 2,933,120 Orms 2,795,425 Andrews 2,568,976 Goldsmith et al 1,551,099 ______________________________________